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1,1,2,2,3,3,4,4-Octaisopropyltetragermetane (iPr2Ge)4 reacted with various alkynes in the presence of palladium complexes at 120 °C to afford 1,2,3,4-tetrahydro-1,2,3,4-tetragermins, Δ4-1,2,3-trigemolene, and 1H-germoles, depending on the kind of alkyne and the palladium complex employed. Terminal alkynes are more reactive than internal ones. Pd(dba)2-ETBP and Pd(acac)2-ETBP systems were found to serve as efficient catalysts. The mechanism of alkyne insertion reactions into the germanium–germanium bonds of (iPr2Ge)4 is discussed.

We propose a novel method for producing high-repetition-frequency short pulses with a halved confocal configuration consisting of an unstable concave–convex resonator in a very high frequency (VHF) discharge-excited slab-type carbon dioxide laser. This method utilizes a fully reflective concave mirror with variable curvature which can be controlled by a piezoelectric device. In general, slab lasers are modulated directly by varying the pulse voltage. However, because plasma fluctuation occurs at the pulse transitions, the repetition frequency is less than 10 kHz and the minimum pulse width is 1 µs. On the other hand, in our method there is no disturbance of the plasma, because the power source is not modulated. There is also little mechanical constraint, because we use a piezoelectric device. As a result, pulse shortening with a high repetition rate is possible. The pulse shape is well reproduced by a three-level rate equation. The mechanism of the method involves changes in ejection efficiency with periodic variation of the radius of curvature of the mirror. Good agreement between observations and calculations was also obtained for the peak power and the pulse width. In this paper we compare measurements with calculations. The possibility of achieving high repetition rate oscillation and pulse shortening by this method is examined. The results confirm the possibility of achieving a repetition frequency between 1.4 kHz and 170 kHz. The shortest pulse width that can be achieved is 160 nanoseconds. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(3): 1–7, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10127

Aim: Brain-derived neurotrophic factor (BDNF) reduces plasma glucose levels in obese db/db diabetic mice and is speculated to produce its effects via the hypothalamus, the regulatory centre of satiety and the autonomic nervous system. The potential effect of BDNF directly on peripheral endocrine organs, however, remains to be clarified. Here we report the effects of BDNF on hormonal secretion from pancreatic islets of Langerhans using their isolated culture. Methods and results: In an immunohistochemical study, mouse pancreatic alpha cells were stained specifically with the anti-TrkB (a specific receptor for BDNF) antibody. After 7 days culture of isolated islets of the normal mouse pancreas, 10 ng/ml BDNF decreased the secretion of glucagon per 6 h significantly less than that of the control (p = 0.016). In contrast, there were no significant changes in insulin secretion or glucagon and insulin contents in the islets cultured under the same conditions. In vivo administration of BDNF (10 mg/kg/day) to normal mice for 7 days significantly decreased their food consumption (p

Double layer films of boron and carbon were prepared by pulsed laser deposition (PLD) on silicon substrates. The film surface morphology was examined by atomic force microscopy (AFM). The chemical composition of the elements, carbon, boron, silicon and oxygen, and bonding state of carbon atoms as a function of the depth from the film surface were analyzed by X-ray photoelectron spectroscopy (XPS) with argon ion sputtering technique. Carbon atoms bonded to boron (CB) were observed as well as carbon atoms bonded to carbon (CC).

Amorphous carbon (a-C) thin films were deposited on Si (111) substrates by an oxygen RF plasma-assisted pulsed laser deposition (PLD) method at an oxygen pressure of 53 mPa, as well as in vacuum and oxygen gas ambient at 53 mPa for comparison, at substrate temperatures (Tsub) between room temperature and 480°C. An X-ray photoelectron spectroscopy (XPS) analysis showed that the highest sp3 content of the film was 58% in oxygen plasma PLD at Tsub=410°C. Under this condition, the film surface morphology was shown to be quite smooth with a roughness of about 5 nm, by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Effects of the oxygen plasma and the substrate temperature on the film properties were examined.

We have previously demonstrated that cutting induces the rapid response of genes for ethylene-responsive transcription factors (ERFs) in leaf strips of tobacco, and that the induction was not interfered but enhanced in the presence of the protein synthesis inhibitor cycloheximide (CHX). In this study, we analyzed the expression of genes for ERFs in tobacco plants by injuring leaf tissues with a hemostat. The results verified that mechanical damage is a trigger for rapid and concurrent induction of both the local and the systemic expression of genes for ERFs in tobacco plants. Further studies on systemic response of ERF genes in response to different severity and position of the wound on a leaf suggested that a threshold value might exist for the magnitude of wound signal to induce systemic activation of these genes. Then, we examined expression of genes for ERFs by analysis in transgenic tobacco plants that harbored reporter genes in which the promoter of the gene for NsERF2, NsERF3 or NsERF4 was fused to a gene for β-glucuronidase. The results suggested that the local and systemic accumulation of ERF mRNAs after wounding was primarily mediated by the rapid activation of transcription of the respective genes. In addition, we found that cycloheximide triggered rapid activation of genes for ERFs which might be mediated via activation of transcription of the genes for ERFs.

Pulse-spray thrombolysis was performed in 2 patients with acute myocardial infarction (AMI) caused by thrombotic occlusion of coronary artery ectasia. Case 1, a 66-year-old woman with an inferior AMI underwent emergency coronary arteriography, which revealed occlusion of an ectatic right coronary artery. Primary balloon angioplasty failed to reestablish distal flow. Urokinase was administered through the pulse-spray infusion catheter (UltraFuse) and intravenous recombinant tissue plasminogen activator was also administered. Angiographic disappearance of the thrombus was observed within 30 min of starting the infusion, and there was only mild irregularity in the ectatic coronary artery. Case 2, a 45-year-old man with an inferior AMI underwent emergency coronary arteriography, which revealed occlusion of an ectatic right coronary artery. TIMI-3 flow was soon obtained after administration of 480,000 units of urokinase through the pulse-spray infusion catheter. There was diffuse right coronary ectasia without angiographic evidence of coronary stenosis. Coronary ectasia sometimes develops into AMI without the coexistence of coronary stenosis. Because a massive thrombus plays a major role, pulse-spray thrombolysis is a possible treatment in coronary artery ectasia with thrombotic occlusion.

In this study, we report on the biocidal activity technique by needle helium plasma irradiation at atmospheric pressure using borosilicate capillary nozzle to apply for the oral surgery. The diameter of needle plasma was less than 50 m, and temperature of plasma irradiated area was less than body temperature. Needle plasma showed emission due to OH and O radical. Raman spectra and methylene blue stain showed yeast cells were inactivated by needle plasma irradiation.

We report on the synthesis of new type of carbon nanostructure filled with metal structure which is austenitic stainless alloy with separation of phase by liquid and solid interfacial arc discharge method. The transmission electron microscopy and nano-beam electron diffraction and energy-dispersive X-ray spectroscopy reveal that the structure of the synthesized carbon nanostructure possessed 3 phases which indicate that single-crystal of Fe2-xCrxO3 at tip part, multi-crystal of Fe2-xCrxO3 at middle part and single-crystal of Fe1-xCrx at root part.

A magnetized coaxial plasma gun (MCPG) is here utilized for deposition on high-melting-point metals. MCPGs have hitherto been studied mostly in the context of nuclear fusion research, for particle and magnetic helicity injection and spheromak formation. During spheromak formation, the electrode materials are ionized and mixed into the plasmoid. In this study, this ablation process by gun-current sputtering is enhanced for metallic thin-film generation. In the proposed system geometry, only ionized materials are electromagnetically accelerated by the self-Lorentz force, with ionized operating gas as a magnetized thermal plasmoid, contributing to the thin-film deposition. This reduces the impurity and non-uniformity of the deposited thin-film. Furthermore, as the ions are accelerated in a parallel direction to the injection axis, vertical implantation of the ions into the substrate surface is achieved. To test a potential application of the developed system, experiments were conducted involving the formation of a buffer layer on hard ceramics, for use in dental materials.

Multiple copies of a cis-acting DNA element, metal-responsive element (MRE) are required for heavy metal-induced transcriptional activation of mammalian metallothionein genes. To approach the regulatory mechanism mediated by these multiple elements, we studied the properties of seven MREs located upstream of the human metallothionein-IIA (hMT-IIA) gene in detail. Transfection assays of reporter gene constructs each containing one of these MREs as the promoter element revealed that only four MREs can mediate zinc response. With respect to the distribution of active MREs over the promoter region, the hMT-IIA gene is largely different from the mouse metallothionein-I gene, suggesting that MRE arrangement is not an important factor for metal regulation. Experiments using various model promoters showed that multiple MRE copies act highly synergistically, supporting the biological significance of the multiplicity. Only the four active MREs efficiently bound the purified transcription factor human MTF-1, and MRE mutants defective in binding this protein lost the ability to support zinc-induced reporter gene expression, strongly suggesting that the direct interaction between human MTF-1 and a set of the selected MREs plays the major role in heavy metal regulation. In protein/DNA binding reactions in vitro, the purified human MTF-1 was activated by zinc but not by other metallothionein-inducing heavy metals, supporting the idea that zinc is the direct modulator of human MTF-1.

A 60-year-old woman who had undergone repair of an atrial septal defect was readmitted to the hospital with dyspnea, abdominal distention, and leg edema 31 months after surgery. An echocardiogram demonstrated massive pericardial effusion. Cardiac catheterization revealed elevation and equilibrium of the 4-chamber diastolic pressure and a dip-and-plateau pattern in the right and the left ventricular pressures. Despite removal of pericardial fluid by pericardiocentesis, the findings and symptoms did not improve. The patient underwent both parietal and visceral pericardiectomy after which striking hemodynamic and symptomatic improvement occurred. Effusive-constrictive pericarditis is uncommon but should be considered in patients with refractory heart failure and massive pericardial effusion showing no improvement after removal of pericardial fluid.

We propose a novel method for producing a short pulse from a VHF-discharge-excitation slab-type CO2 laser using a halved confocal of an unstable concave and convex resonator. This method utilizes a full reflection concave mirror with a function of variable curvature, which can be controlled using a piezo electric device (PZT). Generally, slab-type lasers are modulated directly by varying pulse voltage; however, there is a fluctuation of plasma at the transition of the kHz pulsation. Consequently, the repetitive frequency is less than 10 kHz. On the other hand, the pulse oscillation with our method has a short pulse width of 300 ns and a maximum repetitive frequency of about 58 kHz. The peak power at the pulse oscillation is about 12 times as high as that of the CW oscillation.

The objective of the present study was to evaluate the development to the blastocyst stage in vivo and in vitro of porcine oocytes matured and fertilized in vitro (IVM/IVF). When IVM/IVF oocytes had been transferred to oviducts of synchronized recipients just after IVF, more than 70% of blastocysts recovered after 6 days of transfer had developed to the hatched blastocyst stage with a mean cell number of 181.5 per blastocyst. In contrast, when IVM/IVF oocytes were cultured in vitro for 2 days and then transferred to the oviducts of recipients, or cultured in vitro for 6 days without transfer to oviducts, most recovered blastocysts were still enclosed by zona pellucidae. Mean cell numbers of blastocysts obtained from IVM/IVF oocytes cultured for 2 days in vitro plus 4 days in the oviducts and for 6 days in vitro decreased significantly (P

Hexamethyldigermane, Me3GeGeMe3, reacted with various alkynes in the presence of platinum complexes at 120 °C to afford Z–1,2-bis(germyl)ethenes in moderate to good yields. Terminal alkynes exhibit higher reactivities than internal ones. [Pt(acac)2] and [Pt(dba)2] serve as efficient catalysts, while [Pt(PPh3)4], [PtCl2(PPh3)2], and [Pt(dba)2]-phosphite were found to be inactive. Four- and six-membered cyclic oligogermanes, such as dodecamethylcyclohexagermane, (Me2Ge)6, reacted with alkynes in the presence of platinum catalysts to yield 1,4-digermacyclohexa-2,5-dienes in ca. 30% yield. The reactions of phenylacetylene with 1,2-digermacyclohexa-3,5-dienes afforded the corresponding 1,4-digermacycloocta-2,5,7-trienes in 93% yield. Bis(germyl)platinum complexes having various tertiary phosphine ligands have been prepared as models of a key intermediate in the above mentioned catalytic bis-germylation of alkynes, and their structures have been established by spectroscopic methods and X-ray crystallography. Bi...

Heavily acceptor doped zinc oxide (ZnO) films were deposited on quartz substrates by plasma-assisted pulsed laser deposition (PA-PLD) using a non-sintered target heavily doped with phosphorus or copper and radio frequency induction-coupled nitrogen or oxygen plasma (RF-ICP). The p-type ZnO layer was achieved by a nitrogen acceptor dopant using the technique of plasma-assisted nitrogen (PA-N) pulsed laser deposition. Photoluminescence spectra showed a peak from phosphorus- or copper-bound excitons at about 380 nm and a broad, green defect-related band occurring at about 550 nm. Transmission spectra showed a blue shift of the near-band-edge wavelength and a worsening of transmission by heavily copper-doped zinc oxide.

Ethylene-induced gene expression has been studied in systems in which the biosynthesis of ethylene is stimulated during developmental process such as ripening of fruit, senescence of flower petals, or during pathogen infection. Functional analysis of the promoters of these genes revealed that the ethylene-responsive cis-elements of fruit ripening genes and senescence genes differed from that of defense genes whose expression is induced by ethylene in response to pathogen infection. The ethylene-responsive element identified as the GCC box (AGCCGCC) is commonly found in the promoter region of the ethylene-inducible defense genes. The ethylene responsive element binding factors that interact with the GCC box were demonstrated to be the transcription factors, which respond to extracellular signals to modulate GCC box-mediated gene expression positively or negatively.

We theoretically considered suitable configurations of a fiber grating laser (FGL) to be used in wavelength division multiplexing (WDM) systems. We focused on the effect of composite reflectors where the effect of the front facet of a semiconductor optical amplifier (SOA) is especially significant. We simulated relaxation oscillation frequency and optical power to determine a configuration enabling high bit rates, up to 2.5 Gbit/s. After arriving at a suitable configuration, a packaged FGL has been fabricated. This laser achieves higher output power than any previously reported, and the potential for a rate of 2.5 Gbit/s was confirmed. Compared with a typical 1.55 μm MQW DFB laser, the lasing wavelength temperature dependence is less than half that of a DFB laser. As frequency chirping is remarkably reduced, the power penalty of the FGL is 3 times smaller than that of a DFB laser in transmission experiment with SMF of 70 km.

We report a successful selective technique for preparing single-phase boron-rich silicon borides (SiBx) films employing a pulsed Nd: YAG laser ablation method for multi-layer deposition, the results of which are designed for use in thermo-electric energy conversion device. In this process, SiBx films on silicon substrates were produced by the pulse laser ablation method using a multi-target (single bulk material target: Si and B) in 0.1 Torr argon gas. Nano-meter order silicon particles and boron particles were ablated by different shots numbers of Nd: YAG laser pulses, which deposited several hundred alternating layers of the particles. After the films were heated to about 1670 K for 10 hours under argon gas, x-ray diffraction patterns and electron probe micro analyzer (EPMA) analysis of these films showed a single-phase composition. As a result of the laser ablation process under several processing conditions, thin films of SiB4 or SiB6 are selectively presented about three microns thick and about six centimeters square. The influence of process parameters on morphology, phase diagram, electrical conductivity, thermal conductivity and Seebeck coefficient of the films were also discussed.

Metallothioneins (MTs) are small metal-binding proteins that have a role in the defense against heavy metals. Mammalian MT genes are transcriptionally activated by metals such as Cd and Zn through multiple copies of the metal responsive element (MRE) present in the 5'-flanking region. To examine whether each MRE in a single promoter has a distinct role, we characterized seven MREs located upstream of the human MT-IIA gene. By transient transfection experiments using MRE-driven reporter gene constructs, individual MREs were assayed for the activity to mediate transcription in response to several heavy metal species. Four MREs including MREs a, b, e and g independently mediated reporter gene expression in response to Zn, Cd and Hg, while other MREs were not responsive to any of these metals. These results suggest that the multiplicity of MRE contributes to enhancing its activity, rather than providing functional diversity.

We have investigated the control of photocatalytic behavior under deposited conditions of non-sintered target of different molar ratios with TiO 2 and La 2 O 3 from 1:0 to 1:2 for heavily La doping, and post-annealing temperature from 600 °C to 1000 °C for crystallizing by pulsed laser deposition. We have successfully crystallized heavily La-doped TiO 2 films with post-annealing temperature over 800 °C and with molar ratio of TiO 2 :La 2 O 3 over 1:1 on a quartz substrate. Heavily La-doped TiO 2 films are observed the decomposition of methylene blue and a water-splitting reaction in photocatalytic behavior under Xe light irradiation. When stoichiometric La-doped TiO 2 (TiO 2 :La 2 O 3 = 1: 1) is synthesized with heat-treatment at 900 °C, the best results are obtained under photocatalytic behavior and pure La 2 Ti 2 O 7 crystalline were obtained.

All-trans retinoic acid (ATRA) is a metabolite of vitamin A that is used for molecular targeting therapy of acute promyelocytic leukemia (APL). Most patients with relapse after ATRA therapy show acquired resistance to ATRA, which seems to result from low plasma levels of the drug during therapy. This may be because of increased oxidative catabolism of ATRA or expression of the multidrugresistance gene product. Moreover, we have reported that impaired absorption can lead to lower plasma ATRA levels in patients with gastrointestinal complications [1]. Here, we describe the pharmacokinetics of ATRA in a patient with Crohn’s disease. A 13-year-old girl had been diagnosed with Crohn’s disease 9 months previously after standard endoscopic and histological evaluation. Treatment with steroids and 5-aminosalicyclic acid (5-ASA), as well as parenteral nutrition, led to a gradual improvement of her clinical state. She had no complications, so oral steroids therapy was tapered. Suddenly, she developed fever and blackish diarrhea, and was admitted with severe anemia. The hemoglobin was 6.5 g/dL, so red cell transfusion was performed. Bone marrow aspiration gave a diagnosis of APL. The reverse transcription-polymerase chain reaction detected a PML/RARa fusion chimeric gene. Colonoscopy revealed severe ulceration of the ascending colon and cecum.

To elucidate the role of phospholipase Cbeta (PLCbeta) isozymes in the cerebellum, the distributions of PLCbeta3 and PLCbeta4 were examined in wild-type and PLCbeta4-deficient mutant mice using immunohistochemistry, and the functions were evaluated by measurement of type 1 metabotropic glutamate receptor (mGluR1)-mediated inward current and Ca(2+) mobilization. In wild-type mice, PLCbeta4 was distributed equally in both rostral and caudal cerebellum, while PLCbeta3 was enriched in the caudal versus the rostral cerebellum. In PLCbeta4-deficient mice, there was no measurable inward current or intracellular Ca(2+) elevation in the rostral cerebellum, whereas small responses were observed in the caudal cerebellum. In wild-type mice, the inward current was observed only following the release of caged GTPgammaS, not caged IP(3). These results suggest that the signal transduction machinery, including receptors, G-proteins, PLCbeta3, PLCbeta4, and effectors, form a functional unit, and the deletion of PLCbeta4 alters this unit, markedly changing signal transduction efficacy.

Two requirements should be met in order to develop a practical multimodal interface system , i . e ., ( 1 ) integration of delayed arrival of data and ( 2 ) elimination of ambiguity in recognition results of each modality . This paper presents an efficient and generic methodology for interpretation of multimodal input to satisfy these requirements . The proposed methodology can integrate delayed - arrival data satisfactorily and efficiently interpret multimodal input that contains ambiguity . In the input interpretation the multimodal interpretation process is regarded as hypothetical reasoning , and the control mechanismof interpretation is formalized by applying the assumption - based truth maintenance system ( ATMS ). The proposed method is applied to an interface agent system that accepts multimodal input consisting of voice and direct indication gesture on a touch display . The systemcommunicates to the user through a human - like interface agent's three - dimensional motion image with facial express...

To investigate the involvement of protein kinases in the signaling cascade that leads to hypersensitive cell death, we used a previously established system in which a fungal elicitor, xylanase from Trichoderma viride (TvX), induces a hypersensitive reaction in tobacco (Nicotiana tabacum) cells in culture (line XD6S). The elicitor induced the slow and prolonged activation of a p47 protein kinase, which has the characteristics of a family member of the mitogen-activated protein kinases. An inhibitor of protein kinases, staurosporine, and a blocker of Ca channels, Gd3+ ions, both of which blocked the TvX-induced hypersensitive cell death, inhibited the TvX-induced activation of p47 protein kinase. Moreover, an inhibitor of serine/threonine protein phosphatase alone induced both rapid cell death and the persistent activation of the p47 protein kinase. Thus, the p47 protein kinase might be a component of the signal transduction pathway that leads to hypersensitive cell death, and the regulation of the duration of activation of the p47 protein kinase might be important in determining the destiny of tobacco cells.

Summary To examine the role of reactive oxygen species (ROS) in the signal transduction that leads to hypersensitive cell death, we used a previously established system in which a xylanase from Trichoderma viride (TvX) induces an oxidative burst and cell death in a culture of tobacco cells. Diphenylene iodonium and N-Acetyl-L-cysteine known as an inhibitor of NADPH oxidase and a scavenger of superoxides, respectively, and catalase inhibited the oxidative burst but did not inhibit the induction of cell death. We also found that inhibitors of serine proteases inhibited TvX-induced cell death. These results suggest that there is a signaling pathway in which a serine protease might be responsible for the signal transduction, which is independent of the oxidative burst, that leads to the hypersensitive cell death of tobacco cells.

Two patients with chronic hepatitis C virus (HCV) genotype 2b infection were studied. They responded biochemically to interferon (IFN) but had early virological and later biochemical relapse. The HCV quasispecies equilibrium in these patients was studied by a combination of cloning, sequencing and construction of phylogenetic trees. Another patient with chronic HCV genotype 2b infection was followed every 6 months for 30 months (including one episode of biochemical exacerbation) to serve as the control. Quasispecies equilibrium drifted during IFN therapy but moved back in the direction of the original equilibrium during biochemical relapse. In the control patient, there was no significant drifting throughout the follow-up period. These data suggest that IFN therapy exerts selective pressure on HCV quasispecies equilibrium.

Plants have an excellent mechanism for responding to pathogen invasion by specific and inducible defense reactions, which is often apparent as the so-called hypersensitive reaction (HR). The molecular dissection of the mechanism of HR is difficult since the biological system involves intricate interactions between plant and pathogen. A simplified system, in which suspension-cultured plant cells are synchronously challenged with a single molecular inducer of HR, elicitor, would greatly facilitate studies of the molecular mechanism of HR. Several components involved in elicitor signaling have recently been identified and characterized using the experimental system.

We have attempted to control the photoluminescence spectrum of transparent p-type semiconductor (LaO)CuS to check possibilities of phosphor application using non-stoichiometric thin films prepared by pulse laser deposition method. Two kinds of samples are examined, one is the samples that contain the excess S and the other is the excess Cu. All samples are a single phase without impurities, regardless of heavily doping. Lattice constants for all samples don’t depend on the concentration of excess atoms. Perhaps, this is due to the nature of the layered materials. Introduction of excess atoms leads to change the photoluminescence spectra. The excess S and Cu have much effect on the red and the blue luminescence bands, respectively. We have succeeded in the tuning luminescence band of photoluminescence spectra.

The gas desorption properties of low-activation ferritic steel (F82H) were evaluated by thermal desorption spectroscopy (TDS), and compared with those of austenitic steels (316SS and 316LSS). The major desorbed gas species of F82H were CO, H 2 O, CO 2 and H 2 , The fraction of oxygen-containing species such as CO, CO 2 and H 2 O to the total outgassing amount was 98%. The gas desorption behavior was very similar to the case of 316SS. The gas desorption spectra for F82H show the required prebaking temperature becomes higher than 700 K. For the F82H sample exposed to atmosphere, the gas desorption properties were examined. As the time of exposure increase, desorption amounts of H 2 O and CO largely increased. This increase may be due to the corrosion in atmosphere.

To investigate the functional relationship between the expression of genes for ethylene-responsive transcription factors (ERFs) and the expression of ethylene-responsive genes, we examined the expression of genes for ERFs and the expression of a reporter gene in transgenic tobacco that carried a gene for β-glucuronidase (GUS) under the control of the ethylene-responsive element, which includes four copies of the 11-bp consensus sequence (designated the GCC-box, TAAGAGCCGCC). In strips of leaves of transgenic tobacco, the GCC-box-mediated expression of the reporter gene was induced in response to treatment with ethylene. We also observed the ethylene-independent immediate early induction of the synthesis of mRNAs for ERFs in wounded leaves and the enhancement of this induction by cycloheximide (CHX). Since CHX suppressed the induction of mRNAs for chitinase and GUS by ethylene, protein synthesis de novo was required for induction of the ethylene-dependent GCC-box-mediated transcription of genes. In contrast, the enhancement by CHX of the wound-induced expression of ERFs suggested that no synthesis of new proteins was required for the wounding signal transduction leading to rapid expression of ERFs. Methyl jasmonate did not stimulate the wounding-responsive accumulation of ERF mRNAs, but it reduced such accumulation of mRNAs for ERF1, ERF2, ERF4 and the ethylene-dependent GCC-box-mediated transcription of the reporter gene. Thus, the immediate early induction of the expression of genes for ERFs in strips of tobacco leaves appears to be a novel type of wound-responsive activation of transcription. These results suggested that the expression of ERFs was not sufficient for activation of the GCC-box-mediated transcription but the expression of ERF1, ERF2 and ERF4, and that conversion of these ERFs by ethylene to their active form might be crucial for the GCC-box-mediated activation of the transcription of defense genes.

Treatment of suspension-cultured tobacco (Nicotiana tabacum cv. Xanthi) cells (line XD6S) with fungal proteinaceous elicitors, namely, xylanase (EC 3.2.1.8) from Trichoderma viride (TvX) and xylanase from T. reesei (TrX), induced shrinkage of the cytoplasm, condensation of the nucleus, and, finally, cell death, which were accompanied by typical defense responses that included an oxidative burst and expression of defense genes. A Ca2+ channel blocker, Gd3+, inhibited the typical response of XD6S cells to TvX, which resembled the hypersensitive reaction (HR). These results suggested that the influx of Ca2+ ions plays an important role as a secondary signal. The HR was not observed in TvX-treated tobacco cells (line BY-2) derived from cv. Bright Yellow 2. This result suggests that key features of cultivar-specific interaction can be observed in cultures of tobacco cells. Xylanase from Bacillus circulans (BcX) and B. subtilis (BsX), which has enzymatic properties similar to those of TvX but an amino acid sequence different from that of TvX, did not induce the HR-like response in XD6S cells. These results suggest that the elicitor action of TvX is not due to its ability to hydrolyze cell walls but requires the TvX-specific recognition factors in plant cells. Thus, TvX-induced cell death was not due to some general toxic effect, but seems to be mediated by the activation of a specific cellular signal-transduction cascade that converges with a pathway that activates the intracellular cell death program.

A 62-year-old man had a right renal mass incidentally diagnosed by ultrasonography. Magnetic resonance imaging revealed a well-defined right renal mass with homogenous low-signal intensity on the T1-weighted pulse sequence and heterogeneous high-signal intensity on the T2-weighted pulse sequence. A right nephrectomy was performed. The histological examination showed a myxoma, which is a very uncommon neoplasm in the kidney. Eight cases have been reported previously.

In the five-year period between 1989 and 1993, 87 needlestick accidents occurred among healthcare workers at our hospital. Thirty-seven (43%) of these needlestick accidents involved blood contaminated with hepatitis C virus (HCV), and two of them (5·4%) led to the occurrence of hepatitis C infection. Case 1 was a 43-year-old nurse who was accidentally injured by a needle contaminated with blood from a patient who had cirrhosis and hepatocellular carcinoma due to hepatitis C. Acute hepatitis C occurred after five weeks and HCV RNA was positive after eight weeks. Case 2 was a 33-year-old nurse who was injured by a needle contaminated with blood from a patient who had chronic hepatitis C. Liver function was normal at 11 days after the accident. However, hepatitis C was diagnosed 21 months later after she had successfully given birth to her baby. The nucleotide sequence of the HCV E2/NS1 region was determined in the two patients and the needlestick victims, and phylogenetic trees were constructed by molecular evolutionary analysis. On the basis of these trees, transmission of HCV could be confirmed in both cases. This method of analysis may be useful for confirming the transmission of HCV even long after the event.

BACKGROUND The effects of oxygen free radicals on coronary vasoreactivity remain unknown. OBJECTIVE To examine whether oxygen free radicals increase coronary arterial tone and sensitivity to vasoconstrictor stimulation in closed-chest dogs. METHODS Oxygen radicals were generated by the reaction of xanthine plus xanthine oxidase (XXO) and effects of these substances on the left coronary artery (the percentage diameter change) and on the constrictor effect of ergonovine were examined in vivo in 19 anesthetized, closed-chest dogs by selective coronary angiography. The effects of XXO solution and ergonovine were assessed in a cumulative fashion using 100, 200, and 300 ml XXO and 50, 100, 150, and 200 micrograms ergonovine, in 5 (group I) and 6 dogs (group II), respectively. The effects of XXO on the constrictor responses elicited by 50 micrograms ergonovine were examined in eight dogs (group III). Changes in the vascular endothelium were examined by postmortem electron microscopic examination. RESULTS Oxidative injury alone produced slight constriction of the coronary artery, but the change was not significant. However, ergonovine-induced vasoconstriction was enhanced after administration of 100 and 200 ml (cumulative amount) XXO solution (P < 0.05, group II versus group III). The enhancement was no longer observed after administration of 300 ml (cumulative amount) XXO solution. Scanning and transmission electron microscopies revealed the formation of blebs and ulceration in the coronary endothelium after administration of XXO solution. CONCLUSION These results suggest that oxygen radicals can enhance the ergonovine-induced coronary vasoconstriction in a concentration-dependent manner. There seems to be a critical level of oxygen radicals for the production of the effect.